Is this acceptable English, IYO?

<<Assuming here that by "formal," you mean English that you might expect to see in written form in an article or book or spoken from a prepared text.>>

I disagree somewhat with this definition of formal. I think general tone of discourse has become much less formal over the past fifty years or so, and many books and articles are written in a semi-formal style (not that this is necessarily a bad thing). Basically, formal writing (in my opinion) is limited to academic articles, newspapers--not counting editorials, book reviews, comment pages, etc.--and some non-fiction books--instruction manuals, encyclopedias, but also some 'general interest' books. Also, many exampes of speech from a prepared text are relatively informal; class lectures for example.
I agree with Lazar; there are some verbs for which the middle voice form is one of the standard meanings: 'grow' for example. Other verbs can be used in the middle voice, but are usually informal. Specific fields, like wine tasting perhaps, may include different verbs in the group with standard middle voice meanings.

"Does that mean all native speakers share the same idea of what is formal?"

No.

"I disagree somewhat with this definition of formal."

QED.

Bridget,

I didn't say that my choosing the verb "to sell" in place of "to drink" has anything to do with wine quality.

To me, your sentence suggests that thanks to a low price, or at least a price that is lower than a previous one, the wine bottled in a certain year is being sold to, and therefore drunk by – you usually buy wine in order to drink it, right? – a lot of people, or at least more people than before.

According to this, which is of course my own interpretation, I just think the verb "to sell" sounds better than "to drink". Why? Well, I don't know. That's the way it sounds to *my* ear.

Maybe that's because I feel the buying/selling of an item is related to its price more than what you're going to do with it, in that first comes the action of buying/selling, and only afterwards the action of doing something with what you've bought. If you decide to buy a bottle of wine, first the bottle is being sold to you, and only after that you can drink it.

For what it's worth, that's my two cents.

Achab

I think "the wine is drinking well" refers to its present state regarding drinkability. It's nothing to do with selling.

See the last sentence in the earlier quote, repeated here for ease:

Castello di Ama, Chianti Classico, Bellavista, 1998: Yet another excellent wine from Ama, this full bodied, deep royal purple wine has plenty of smooth flavors, just the right hint of the large oak casks in which it was aged and complex berry, cherry, floral, earthy and spicy aromas and flavors that play nicely on the palate. Long lingering, the wine is drinking well now but will be at its best only from 2003 - 2007. Score 92+.

I agree with Bridget.

"It is drinking well now but also has the structure to improve in complexity with a few years in the cellar."

It's fine to drink the wine now,but will be better if kept till a later period.

Bridget,

It is pretty obvious that "to drink well" refers to wine quality in your latest example. There's a fairly clear context that tells us about the fact that if you have wine age for a certain period, it will then taste better.

In your previous example, though, there wasn't a context like that. Wine aging was no mentioned, while there was a short reference to prices.

This said, I still think that your original example, even if it may refers to wine quality, it *looks* like it refers to sales, or at least to sales as well.

Of course, that's the way the sentence sounds *to me*. I don't believe there are authoritative opinions out there and I don't pretend mine to be one.

With every good wish,

Achab